Washer.



W. l'. KIRK.

WASHER. v APPL|cAT|oN-r|LEn JAN. l?. 1914.

l 153,232., j' Patented Sept. 14.1,v 191.5.

'll f on line 2-2 in pNrrRn sIAfrRs -rA'rRNfr orme-n WALTER I. KIRK, or CHICAGO, ILLINOIS, AssICNoR rro LYON a HRALY, or CHICAGO,

' ILLINOIS, A CORPORATION or ILLINOIs. v 1

WASHER.

Patented` Sept. la, 1915.

Application mea January 17, 1914.. serial No. 812,656.

To all whom, t may concern Be it known that I, WALTER I. KIRK, a y

citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented a certain lnew and useful Improvement in Washers, of which the following is a full, clear, concise, and exact description, reference being had to the accompanying drawings, forminga part of this specification.

My invention relates towashers orlike devices, and especially to ay kind of washer particularly adapted for use in connection with devices which are apt to expand, as for example the neck of a harp, which being wood of considerable thickness is apt to expand or contract in accordance with changes in atmospheric conditions.

Prominent objects of the invention are'to provide a simple and practical form of washer; to permit parts held by the washer to expand moderately without damaging effects; to permit a tight iit and clamping action to be secured notwithstanding the arrangement made to take up expansion; and to secure the foregoing and other desirable results in a simple and expeditious manner.

In the accompanying drawings Figure 1 is an elevation of the upper portion of a harp provided with bolts having washers embodying my invention; Fig. 2 is a cross section Fig. 1,Fig. 2 being on an enlarged scale; Fig. 3 kis a plan view on a still larger scale of the washer alone.

In the drawings I show uprights 1 and 2 and neck 3 of a harp which may be ofany usual or ordinary construction. The neck 3 is provided with a metallic plate 4, usually made of brass and usually called the action plate. This action plate is held in position by suitable studs or bolts 5 5, the strings 6-6 running to tuning'pins 7-7. In Fig. 2 a washer 8 is shown between the head 5a of one of said bolts 5, and the plate 4:. These washers 8-8 are especially made to permit transverse or crosswise expansion on the part of .the wood in the neck' 3, and at thek same time to permit the bolt or stud to be drawn sufiicie'ntly tight to insure a tight t and proper operation on the part of the harp. To such end the Ywashers 8-8 are desirably constructed of a metal shell-like structure comprising a top portion 9 and a bottom portion 10 with an intermediate layer 11 of some moderately yielding preferably fabric material, such for example as woolen felt. rIhe device is preferably made by stamping the metal shell out of a single piece of material, the felt being interposed 1n position in the operation. Although when shown in enlarged view as in Figs. 2 and 3 this washer seems to have a considerable amount ofintermediate fabric 11, in actual practice the amount is not great but simply f sufficient to allow a moderate expansion of the wood of the neck 3 without forcing off the head of the stud 5. In actual practice I have found a harp made with washers like this holding the action plate in place will remain undamaged in varying conditions of air and moisture, whereas under the same conditions the heads of screws or bolts without washers of this kind have been forced of by the expansion of the wood. Of course'the size and proportions of the washers 8 may be varied according to circumstances. As shown in Figs. 2 and 3, the back wall l0 is made somewhat concave and the front wall 9 somewhat convex, whereby better adjustment and distribution will be secured as well as making further allowance for expansion of the wood of the neck.

It will be understood that changes and modifications may be made without departing from the spirit of the invention. V

What I claim is:

1. A washer comprising opposing metallic members one of which is concave and the other convex, said members'being connected together at their outer annular edges, but separatedfrom` one another at their inner annular edges, andan intermediate layer of yielding material interposed between said members.

`2. `AA device of the class specied comprising a shell having a concave back wall and a convex front-Wall, in combination with a. In Witness whereof, I hereunto subscribe layer of yielding material between said my name this 30th day of December, A. D.,

Walls.

3. A device of theclass speciedvcompris- WALTER I. KIRK.

5 ing wsh'ell having a back concafve Weil and Witnesses:

a. front convex Wall, and a layer of ,Woolrfelt v, n A. L. JONES, between said Wells. H. A. JONES.

Copies of this patent may befobta'ined foriivecentseeaoh, -by-addressing t'he Commissioner of Patents, Washington, IJ. C. 

